"Sola Scriptura" is Latin for "Scripture alone." It was one of the two main tenants of the Protestant reformers of the 16th century, the other being "Sola Fide" or "faith alone." Their claim then, and still the claim of Protestant denominations today, was that the Scriptures alone were all that is necessary or infallible. There is some trouble pinning down an exact definition of "Sola Scriptura" as there many differing views on exactly what the term encompasses. Catholics too place great emphasis on the Scriptures as we believe it is the infallible, inspired Word of God. Yet, Catholics believe that not only is Scripture necessary, but also Sacred Tradition and the teaching authority of the Church.
There are many questions that Catholics have always had with regard to the 16th century innovation of the Reformers that Scripture alone was all that was necessary to understand Christian truths. Many of these questions do not have answers and never have. Some have answers that even Protestants would agree are not as strong as they would like. Listed below are the questions and why they are important questions.
1) Where does the Bible teach what books belong in the Bible?
Why it's important: Its important because if Scripture doesn't teach what books are among the canon of Scripture, then one who goes by Scripture alone must concede they refer to an authority outside of Scripture to even determine what Scripture is. There is no inspired table of contents, when it reads "The Gospel According to Matthew" that is just editorial work added centuries later.
Some may claim that Scripture is self -attesting. In otherwords, it says it is Scripture. Many books claim to be divinely inspired including the Koran, Book of Mormon, etc...... I could do the same with this writing, but that would not make it so. Also, there are many books of the Bible that nowhere claim to be inspired. Would we have to throw them out based on this type of reasoning?
Some may claim they feel it.....when they read Scripture. A kinda burning in the bosom. Let me remind anyone who has forgotten that during the first four centuries after Christ's death and resurrection, that there were ongoing disputes among Christians about exactly what and what wasn't Scripture. These where Christians being martyred for the faith. Same with the Protestant Reformers. Martin Luther, in addition to throwing out the seven books of the Old Testament, also threw out at least four books of the New Testament including Hebrews, Jude, James and Revelations. Why? He claimed they weren't Scripture. He writes his reasons in the preface to his German translation of the New Testament in 1522. Think about this, Luther proclaimed "Sola Scriptura", yet he couldn't even RECOGNIZE Scripture based on modern Protestant canons. Once again, where does Scripture infallibly teach what books are Scripture? If it does not, one most look outside of Scripture to answer this fundamental question.
2) Where does the Bible teach "Sola Scriptura?"
Why it's important: It's important because if Scripture doesn't teach "Sola Scriptura" then, oddly enough, its unbiblical. Think about this! Where does Scripture teach that it alone is infallible? Nowhere. Where does Scripture teach that it alone is all that is necessary for understanding Christian truth? The Catholic would say nowhere, but, in fairness, according to many Protestants that I have spoken with, in two places.
Some claim that Revelation, chapter 22, verse 18-19, teaches Sola Scriptura, which reads:
"I warn everyone who reads the prophetic words in this book: if anyone adds to them, God will add to him the plagues described in this book, and if anyone takes away from the words in this prophetic book, God will take away his share in the tree of life and in the holy city described in this book."
Why this is an inaccurate application of Scripture: Because God tells us the same thing in Deuteronomy Chapter 4, verse 2 when he writes:
"......you shall not add to what I have commanded you nor subtract from it...."
If we give the same interpretation to the Old Testament as some Protestants do to the New Testament, then we never could have added the New Testament to the canon of Scripture, much less any inspired book written after Deuteronomy. Think about his. Most biblical scholars agree that the apostle John wrote Revelation last, after all the other books. It was written by itself possible as far as fifty years after Matthew's Gospel. If we go with the Protestant interpretation of this verse, then we could not "add" the rest of the New Testament, much less the Old Testament, to it.....because it would be adding to the "words of this prophetic book."
The clue to the proper understanding of this verse is found in John's use of the word "prophetic." He uses it twice to distinguish this book from others. Are all books of Scripture considered "prophetic" books. No. Most Protestants would agree to this. When the apostle John wrote these words, they were certainly just as inspired then as they are now. Yet the "prophetic" book of Revelation that John wrote was not included in the canon of Scripture at the time. It was centuries later until all the other books of Scripture were "added" to the book of Revelations to make up our New Testament canon. One cannot strictly claim that nothing can be "added" to the book of Revelation or they would have to limit their canon to just one book.........Revelation.
The other popular and apparently more compelling argument for the Bible teaching "Sola Scriptura" comes from Paul's second letter to Timothy (2Tim 3:16-17) in which he writes in verse 16-17:
"All Scripture is inspired by God and is useful for teaching, for refutation, for correction, and for training in righteousness, so that the one who belongs to God may be complete, equipped for every good work."
Why this is an inaccurate application of Scripture: First, Catholic too believe"all Scripture is inspired by God and is useful for teaching, for refutation, for correction, and for training in righteousness." We say "Amen" right along with Scripture and our Protestant brothers and sisters. We also believe Scripture is "useful" to say the least. But this certainly doesn't teach "Sola Scriptura." The real debate begins with the next line that reads: "so that the one who belongs to God may be complete, equipped for every good work." Nowhere does Paul say that ONLY Scripture can make one "complete", but that Scripture is an essential part of this. If the reader thinks I am providing a false reading of this, I refer them to the equally inspired words of St. James who, in chapter one, verse 4, of his epistle, tells us:
"And let perseverance be perfect, so that you may be perfect and complete, lacking in nothing."
So which is it? Does Scripture alone make one "complete?" Or does "Perseverance" alone make one "complete?" The obvious and most biblical answer is that both do. Paul nowhere says "Scripture alone", but rather, realizing that Scripture is a necessary part of many things need to be "complete" does give it it's due. Also, as the famous convert Cardinal John Henry Newman once said in regard to this verse "if this proves Sola Scriptura it proves to much." Why? Because the verse previous (2Tim 3:15) points out that Paul is referring specifically to the Scriptures of Timothy's "infancy"(i.e. the Old Testament). Certainly Paul's words were just as inspired at the time he wrote them as they are now. Yet the New Testament canon didn't exist then, not to mention many of the other Scriptures of the New Testament. If we take Paul's words literally, then he would be claiming "Sola Old Testament." No Christian would agree with that.
There are many other problems with trying to apply this verse to support "Sola Scriptura." For example, how does one know they belong to God? If they believe they do, why so much disagreement among Protestants over what Scripture means? According to the United Nations, there are over 28,000 Protestant denominations each claiming to go by "Sola Scriptura" yet they all disagree to greater and lesser extents over exactly what Scripture is saying on issues of salvation, baptism, communion, etc..... They may claim the Holy Spirit guides them, but with so much confusion, we must remind the reader that the Holy Spirit is not the author of confusion.
Our Protestant brothers and sisters are to be commended for their love of God's Word. Many Catholics would do well to show the same passion for the Word of God as do many Protestants I have met. But ultimately, one must remember that the New Testament Church existed before the New Testament. The Old Testament Church existed before the Old Testament. The Scriptures were entrusted to the Church to preserve them and correctly interpret them. Not each and every individual.